Minced fish ink of bighead carp low-fat emulsion gel as well as preparation method and application of minced fish ink

Abstract

The invention provides bighead carp low-fat emulsion gel surimi printing ink as well as a preparation method and application of the bighead carp low-fat emulsion gel surimi printing ink. The method comprises the following steps: preparing a 1-4% (w / v) BCM particle suspension or BCS particle suspension by using a 200-1000mmol / L KCl solution, magnetically stirring, adjusting the pH value of the suspension to be neutral, hydrating for 24 hours, adding soybean oil, and homogenizing to obtain BCMPEs gel or BCSPEs gel; the preparation method comprises the following steps: carrying out unfreezing and blending pretreatment on minced bighead carp, adding 10-30% (w / w) of BCMPEs gel or BCSPEs gel, and uniformly mixing to obtain the minced bighead carp low-fat emulsion gel surimi ink. By optimizing a formula and a preparation process, the 3D printing material has good 3D printing adaptability, and a high-precision and high-stability product can be printed; the characteristics of minced fillet gel are improved, low fat is realized, and the nutritional and edible requirements of special crowds are met.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, and in particular to a bighead carp low-fat emulsion gel surimi ink, a preparation method and application thereof. Background Art

[0002] As people's demand for food quality and personalization continues to increase, the application of 3D printing technology in the food field has gradually attracted attention. As a popular food, surimi products have great development potential when combined with 3D printing technology. However, traditional surimi inks currently have many problems in the 3D printing process, such as low printing accuracy, poor product stability, and difficulty in meeting the nutritional and edible needs of special groups (such as patients with dysphagia, young children, and the elderly). At the same time, existing surimi products often have problems such as high fat content, which does not conform to the current trend of healthy eating. Therefore, it is of great practical significance to develop a surimi ink with good 3D printing adaptability, low fat content and excellent gel properties. Summary of the Invention

[0003] In order to solve the problems mentioned in the background technology, the present application provides a small carp low-fat emulsion gel fish paste ink and its preparation method and application.

[0004] In a first aspect of the present invention, a surimi ink of bighead carp low-fat emulsion gel is proposed, wherein the surimi ink has a moisture content of 75-90%, and is made of bighead carp surimi and 10%-30% by weight of bighead carp low-fat Pickering emulsion gel, and the bighead carp low-fat Pickering emulsion gel is any one of BCMPEs gel and BCSPEs gel.

[0005] Furthermore, the weight fraction of the bighead carp low-fat Pickering emulsion gel is 20%.

[0006] Furthermore, the weight fraction of the BCMPEs gel is 20%.

[0007] In the above technical solution, by adopting a specific water content and a ratio of bighead carp surimi to bighead carp low-fat Pickering emulsion gel, the surimi ink has suitable rheological and physical properties, which is conducive to subsequent 3D printing. At the same time, it achieves low fat content, meeting the needs of specific groups for healthy food.

[0008] A second aspect of the present invention provides a method for preparing a surimi ink of a bighead carp low-fat emulsion gel, the method comprising:

[0009] S1, preparing a 1-4% (w / v) concentration of BCM particle suspension or BCS particle suspension using 200-1000 mmol / L KCl solution, adjusting the suspension to a neutral pH after magnetic stirring, adding soybean oil after hydration for 24 hours, and homogenizing to obtain a BCMPEs gel or BCSPEs gel;

[0010] S2, after thawing and crushing the bighead carp surimi, adding 10%-30% (w / w) BCMPEs gel or BCSPEs gel and mixing until uniform, to obtain bighead carp low-fat emulsion gel surimi ink.

[0011] In the above technical solution, the preparation method, through precise steps and parameter control, can stably produce surimi ink with specific properties. In step S1, the suspension is prepared using a specific solution and then hydrated, providing a good foundation for the subsequent formation of the surimi ink. In step S2, the pretreatment of the bighead carp surimi and its mixing with the bighead carp low-fat Pickering emulsion gel ensures the full integration of the surimi ink components, ensuring the uniformity and stability of the product's performance.

[0012] Furthermore, step S1 also includes adding soybean oil and 5-20 U / g of transglutaminase after 24 hours of hydration, followed by homogenization to obtain a BCMPEs gel or BCSPEs gel. Transglutaminase can promote cross-linking reactions between protein molecules, and the degree of cross-linking can be precisely controlled within a dosage range of 5-20 U / g.

[0013] Furthermore, the pretreatment of step S2 includes thawing the frozen bighead carp surimi at 4°C for 12 h, cutting into 2×2×2 cm 3 The cubes were pounded in a mortar for 5 minutes, then pounded for another 15 minutes with 2.5% (w / w) table salt. This pretreatment, by precisely controlling the thawing temperature and time, the size of the cubes, the pounding process, and the amount of salt added, effectively activated the protein activity in the surimi, allowing it to better bind with the bighead carp low-fat Pickering emulsion gel when subsequently mixed. This increased the gel strength and overall quality of the surimi ink, while also improving its processing properties.

[0014] Furthermore, the preparation method of BCMPEs gel is implemented by selecting any one of the three steps a, b, and c:

[0015] In step a, a 1%-4% (w / v) BCM particle suspension was prepared using a 600 mmol / L KCl solution. After magnetic stirring, the pH of the suspension was adjusted to neutral. After hydration for 24 hours, soybean oil was added at an oil-water ratio of 5:5 (v / v), and the BCMPEs gel was obtained after homogenization.

[0016] Step b: Prepare a 2% (w / v) concentration of BCM particle suspension using 200-1000 mmol / L KCl solution. After magnetic stirring, adjust the pH of the suspension to neutral. After hydration for 24 hours, add soybean oil at an oil-water ratio of 6:4 (v / v), and homogenize to obtain BCMPEs gel.

[0017] Step c: A 2% (w / v) BCM particle suspension was prepared using a 600 mmol / L KCl solution. After magnetic stirring, the pH of the suspension was adjusted to neutral. After hydration for 24 hours, 5-20 U / g of transglutaminase and soybean oil with an oil-to-water ratio of 6:4 (v / v) were added, and the suspension was homogenized to obtain a BCMPEs gel.

[0018] Furthermore, the preparation method of BCSPEs gel is implemented by selecting any one of the three steps a', b', and c':

[0019] a' step, using 600 mmol / L KCl solution to prepare a 1%-4% (w / v) concentration of BCS particle suspension, after magnetic stirring, adjust the suspension to a neutral pH, hydrate for 24 hours, add soybean oil at an oil-water ratio of 5:5 (v / v), and homogenize to obtain BCSPEs gel;

[0020] b' step, using 200-1000 mmol / L KCl solution to prepare a 2% (w / v) concentration of BCS particle suspension, after magnetic stirring, adjust the suspension to a neutral pH, hydrate for 24 hours, add soybean oil at an oil-water ratio of 6:4 (v / v), and homogenize to obtain BCSPEs gel;

[0021] In step c', a 2% (w / v) concentration of BCS particle suspension was prepared using 600 mmol / L KCl solution. After magnetic stirring, the pH of the suspension was adjusted to neutral. After hydration for 24 hours, 5-20 U / g of glutamine aminotransferase and soybean oil with an oil-to-water ratio of 6:4 (v / v) were added, and BCSPEs gel was obtained after homogenization.

[0022] In this technical solution, the optimized preparation of BCMPEs and BCSPEs gels was achieved by precisely controlling protein concentration, ionic strength, and transglutaminase activity. A 1%-4% (w / v) concentration of BCM and BCS particle suspensions makes the gels suitable for 3D printing scenarios with varying fineness and stability requirements. A KCl solution concentration of 200-1000 mmol / L improves both the mouthfeel and 3D printing stability of the surimi gels. A transglutaminase dosage of 5-20 U / g regulates the degree of gel cross-linking, meeting the quality requirements of diverse food products, from soft foods to high-strength gels. This expands the application range and overall performance of BCMPEs, BCSPEs, and surimi inks in food 3D printing and product manufacturing.

[0023] Furthermore, the preparation method of BCM particles includes:

[0024] S11, taking 150-250 g of white muscle from the back of bighead carp, adding buffer 1 (pH 7.5) prepared from 0.08-0.12 mol / L KCl and 20 mmol / L Tris-HCl, homogenizing, filtering, and centrifuging to obtain precipitate 1;

[0025] S12, suspending the precipitate 1 in a buffer 2 prepared from 0.4-0.5 mol / L KCl, 4-6 mmol / L β-ME, 0.18-0.22 mol / LMg(CH3COO)2, and 0.8-1.2 mmol / L EGTA at pH 6.8-7.0, and adding ATP-Na2 to a final concentration of ATP-Na2 of 8-12 mmol / L to obtain a mixed solution;

[0026] S13, incubating the mixture at 3-5°C for 80-100 minutes, centrifuging, and diluting the collected supernatant with 1 mmol / L KHCO3. The mixture was placed at 4°C for 1.5-2.5 hours, and then centrifuged to obtain precipitate II.

[0027] S14, suspending the precipitate 2 in a buffer solution 3 at pH 7.5 containing 0.45-0.55 mol / L KCl and 4-6 mmol / L β-ME, and placing it at 4°C for 10 min. Then, 1 mmol / L KHCO3 was added for dilution, and MgCl2·6H2O solid powder was added to a final concentration of 18-22 mmol / L. The mixture was allowed to stand at 4°C overnight to obtain a BCM suspension.

[0028] S15, collecting the centrifugal precipitate of the BCM suspension and freeze-drying it to obtain BCM particles.

[0029] In the above technical scheme, the BCM particle preparation method effectively extracts and purifies the effective ingredients in bighead carp muscle and removes impurities through multi-step buffer treatment, centrifugal collection, and incubation at specific temperature and time, thereby obtaining high-purity and stable performance BCM particles, laying the foundation for the preparation of high-quality BCMPEs gel and fish paste ink.

[0030] Furthermore, the preparation method of BCS particles includes:

[0031] S11', cleaning the bighead carp, removing the head, tail and internal organs, and then collecting the meat to obtain bighead carp minced meat;

[0032] S12′, rinsing the minced meat with ice water at a material-liquid ratio of 1:5 (w / v) for 30-60 minutes, repeating three times, dehydrating, adding 4% (w / w) sorbitol, 4% (w / w) sucrose, 0.2% (w / w) sodium pyrophosphate, and 0.2% (w / w) sodium tripolyphosphate, and chopping and mixing uniformly;

[0033] S13', BCS particles were obtained after freeze-drying.

[0034] In the above technical solution, this BCS particle preparation method effectively removes impurities and undesirable components in bighead carp minced meat through steps such as washing, rinsing, adding specific additives, and freeze-drying. At the same time, additives are used to improve the performance of the minced meat. The obtained BCS particles have good stability and functionality, which is conducive to the subsequent preparation of BCSPEs gel and fish paste ink.

[0035] Furthermore, during the preparation of BCMPEs gel and BCSPEs gel, soybean oil was added at an oil-water ratio of 5:5-6:4 (v / v), and homogenized at 22,000 rpm for 2 minutes to obtain a bighead carp low-fat Pickering emulsion gel. By precisely controlling the oil-water ratio and homogenization parameters, the soybean oil was fully dispersed in the system, allowing it to blend better with other ingredients, forming a stable Pickering emulsion and gel. This ensured the quality and performance of the bighead carp low-fat Pickering emulsion gel, thereby improving the overall quality of surimi ink.

[0036] The third aspect of the present invention proposes the application of a fish paste ink of a bighead carp low-fat emulsion gel, and the application of the fish paste ink of the bighead carp low-fat emulsion gel described in the first aspect or the fish paste ink of the bighead carp low-fat emulsion gel prepared by the preparation method described in the second aspect in 3D printing.

[0037] Furthermore, the 3D printing parameters include nozzle diameter of 1.55 mm, syringe barrel diameter of 28 mm, layer thickness of 1.55 mm, wall thickness of 4.65 mm, bottom and top layer thickness of 3.1 mm, filling density of 80%, and printing speed of 15 mm / s.

[0038] Compared with the prior art, the present invention has the following advantages:

[0039] (1) The surimi ink prepared by the present invention, which is a low-fat emulsion gel of bighead carp, has significantly improved 3D printing adaptability through a specific formulation and preparation process. The ink's apparent viscosity and storage modulus (G') are reduced, making extrusion smoother. Furthermore, the ink has a high thixotropic recovery ability, enabling the printing of products with stable structure, high precision, and regular shape. This overcomes the problems of discontinuous extrusion and uneven surface that are common in existing surimi inks used in 3D printing.

[0040] (2) The bighead carp low-fat Pickering emulsion gel contained in the surimi ink of the present invention effectively improves the comprehensive performance of the surimi gel. The bighead carp low-fat Pickering emulsion gel can fill the gaps in the surimi gel network, enhance the gel network density, increase the water holding capacity (WHC), reduce the cooking loss (CL), and improve the whiteness of the gel. At the same time, it can optimize the gel strength, hardness, and chewiness to a certain extent, making the surimi gel more advantageous in taste and quality.

[0041] (3) The fish paste ink of the bighead carp low-fat emulsion gel of the present invention and its products are low-fat, and relevant tests (such as IDDSI test) show that the fish paste gel with an appropriate amount of gel added can be classified as a level 6 / 7 (soft and bite-sized / easy to chew) food suitable for patients with dysphagia, providing a functional food option that meets nutritional needs and is easy to eat for young children, the elderly and people with dysphagia, filling the relevant market gap.

[0042] (4) The present invention not only provides new high-quality materials for food 3D printing and promotes the innovative application of 3D printing technology in the food industry, but also its preparation method and technical ideas can be extended to other aquatic products or food fields. It has good versatility and application prospects, and provides a new approach and theoretical support for the development of new products in the food industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The accompanying drawings provide a further understanding of the embodiments and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate the embodiments and, together with the description, serve to explain the principles of the invention. Other embodiments and many of the intended advantages of the embodiments will be readily apparent as they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale with respect to each other. Like reference numerals designate corresponding similar parts.

[0044] Figure 1 This is a flow chart of a method for preparing a bighead carp low-fat emulsion gel surimi ink according to one embodiment of the present invention;

[0045] Figure 2 The rheological properties of the surimi ink prepared according to Examples 1-3, the experimental group, the blank group and the control group of the present invention;

[0046] Figure 3 3D printed product models of surimi ink according to Examples 1-3, experimental group, blank group and control group of the present invention;

[0047] Figure 4 The results of 3D printing accuracy and stability analysis of surimi ink according to Examples 1-3 of the present invention, the experimental group, the blank group, and the control group are shown;

[0048] Figure 5 The water holding capacity and cooking loss of the surimi gel according to Examples 1-3 of the present invention, the experimental group, the blank group and the control group;

[0049] Figure 6 The T2 relaxation time curves, T2 peak area ratios and nuclear magnetic resonance imaging of the surimi gels of Examples 1-3, the experimental group, the blank group and the control group according to the present invention;

[0050] Figure 7 The confocal laser scanning microscopy (CLSM) imaging results of the surimi gels of Examples 1-3, the experimental group, the blank group, and the control group according to the present invention;

[0051] Figure 8 Scanning Electron Microscopy (SEM) images of surimi gels according to Examples 1-3, the experimental group, the blank group, and the control group of the present invention;

[0052] Figure 9 The surimi gels of Examples 1-3, the experimental group, the blank group and the control group according to the present invention were subjected to a dysphagia food texture assessment test conducted according to the International Dysphagia Diet Standardisation Initiative (IDDSI). DETAILED DESCRIPTION

[0053] The following will be combined with the accompanying drawings of the present invention to clearly and completely describe the technical solutions in the embodiments. Similar component numbers in the drawings represent similar components. Obviously, the embodiments described below are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0054] It will be understood that when used in this specification and the appended claims, the terms “comprises” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0055] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the present invention. As used in the specification and appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0056] In the first aspect, the present invention provides a flow chart of a method for preparing a low-fat emulsion gel of bighead carp surimi ink, as shown in FIG. Figure 1 As shown, the method includes:

[0057] S100, a 1-4% (w / v) concentration of BCM particle suspension or BCS particle suspension is prepared using 200-1000 mmol / L KCl solution. After magnetic stirring, the pH of the suspension is adjusted to neutral. After hydration for 24 hours, soybean oil is added and homogenized to obtain BCMPEs gel or BCSPEs gel.

[0058] In some specific embodiments, a 1-4% (w / v) concentration of bighead carp myosin (BCM) particle suspension or a bighead carp surimi (BCS) particle suspension was prepared using 200-1000 mmol / L KCl solution, and the suspension was magnetically stirred for 2 h. The pH of the suspension was adjusted to 7 with 1 mol / L HCl and NaOH solutions, and the suspension was hydrated at 4°C for 24 h. Soybean oil was added at an oil-water ratio of 5:5-6:4 (v / v), and the suspension was homogenized at 22,000 rpm for 2 min to prepare a bighead carp myosin-stabilized Pickering emulsion (BCMPEs) gel and a bighead carp surimi-stabilized Pickering emulsion (BCSPEs) gel.

[0059] In some specific embodiments, the method for preparing BCM particles comprises:

[0060] S101, taking 150-250 g of white muscle from the back of bighead carp, adding buffer 1 (pH 7.5) prepared from 0.08-0.12 mol / L KCl and 18-22 mmol / L Tris–HCl, homogenizing, filtering, and centrifuging to obtain precipitate 1;

[0061] Specifically, 200g of bighead carp dorsal white muscle was weighed and added with 10 volumes of buffer 1 containing 0.1mol / L KCl and 20mmol / L Tris-HCl (pH 7.5). The mixture was homogenized in a food processor for 2 minutes. The homogenate was incubated at 4°C for 15 minutes, then filtered to remove the muscle membrane. The mixture was then centrifuged at 10,000×g for 20 minutes, the supernatant discarded, and the precipitate collected.

[0062] S102, suspending the precipitate 1 in a buffer 2 prepared from 0.4-0.5 mol / L KCl, 4-6 mmol / L β-ME, 0.18-0.22 mol / LMg(CH3COO)2, and 0.8-1.2 mmol / L EGTA at pH 6.8-7.0, and adding ATP-Na2 to a final concentration of 8-12 mmol / L ATP-Na2 to obtain a mixed solution;

[0063] Specifically, the precipitate 1 was suspended in 5 volumes of 20 mmol / L Tris-HCl buffer (pH 6.8, containing 0.45 mol / L KCl, 5 mmol / L β-ME, 0.2 mol / L Mg(CH3COO)2, 1 mmol / L EGTA), i.e., buffer solution 2, and ATP-Na2 was added to make the final concentration of ATP-Na2 reach 10 mmol / L to promote the dissociation of myosin and actin.

[0064] S103, incubating the mixture at 3-5°C for 80-100 minutes, centrifuging, and diluting the collected supernatant with 1 mmol / L KHCO3. The mixture was placed at 4°C for 1.5-2.5 hours, and then centrifuged to obtain precipitate II.

[0065] Specifically, after being placed at 4°C for 90 minutes, the mixture was centrifuged at 10,000×g for 20 minutes, the collected supernatant was diluted with 7 volumes of 1 mmol / L KHCO 3 , placed at 4°C for 2 hours, and then centrifuged at 10,000×g for 20 minutes to collect the precipitate to obtain precipitate II.

[0066] S104, precipitate 2 was suspended in buffer 3 at pH 7.5 containing 0.45-0.55 mol / L KCl and 4-6 mmol / L β-ME, and the suspension was placed at 4°C for 10 min. 1 mmol / L KHCO3 was added for dilution, and MgCl2·6H2O solid powder was added to a final concentration of 18-22 mmol / L. The suspension was allowed to stand at 4°C overnight to obtain a BCM suspension.

[0067] S105, collecting the BCM suspension centrifugal precipitate, and freeze-drying to obtain BCM particles.

[0068] Specifically, the resulting precipitate (II) was suspended in 2.5 volumes of 20 mmol / L Tris-HCl buffer (pH 7.5, containing 0.5 mol / L KCl and 5 mmol / L β-ME), i.e., buffer (III). After incubation at 4°C for 10 minutes, it was diluted with 5 volumes of 1 mmol / L KHCO₃. MgCl₂·6H₂O powder was added to a final concentration of 20 mmol / L, and the mixture was incubated at 4°C overnight. The next day, the precipitate was collected by centrifugation at 10,000 × g for 20 minutes to obtain purified bighead carp myosin, which was then freeze-dried to obtain BCM particles.

[0069] In some specific embodiments, in step S100, soybean oil and 5-20 U / g of transglutaminase are added after hydration for 24 hours, and BCMPEs gel or BCSPEs gel is obtained after homogenization.

[0070] Specifically, the preparation method of BCMPEs gel is implemented by selecting any one of the three steps a, b, and c:

[0071] In step a, a 1%-4% (w / v) BCM particle suspension was prepared using a 600 mmol / L KCl solution. After magnetic stirring, the pH of the suspension was adjusted to neutral. After hydration for 24 hours, soybean oil was added at a 5:5 (v / v) oil-water ratio, and homogenization was performed to obtain a BCMPEs gel. Varying the concentration of the BCM particle suspension from 1%-4% (w / v) effectively modulated the rheological properties of the gel, enabling the surimi ink prepared from this gel to precisely match the required fluidity and structural stability during 3D printing, adapting to different printing requirements. This makes it suitable for a wide range of 3D printing scenarios, from intricate shapes to large, robust structures.

[0072] In step b, a 2% (w / v) BCM particle suspension is prepared using a 200-1000 mmol / L KCl solution. After magnetic stirring, the pH of the suspension is adjusted to neutral. After hydration for 24 hours, soybean oil is added at a 6:4 (v / v) oil-water ratio, and homogenization is performed to obtain a BCMPEs gel. Adjusting the KCl solution concentration from 200-1000 mmol / L affects the dispersion and interactions of the BCM particles, modifying the microstructure of the surimi gel and improving its taste. It also enhances the stability of the surimi ink during 3D printing and reduces the risk of deformation during printing.

[0073] In step c, a 2% (w / v) BCM particle suspension was prepared in a 600 mmol / L KCl solution. After magnetic stirring, the suspension was adjusted to a neutral pH. After hydration for 24 hours, 5-20 U / g of transglutaminase and soybean oil at a 6:4 (v / v) oil-water ratio were added, and homogenization was performed to obtain a BCMPEs gel. The 5-20 U / g transglutaminase dosage precisely controlled the degree of protein cross-linking, meeting the quality standards of various products, from soft foods for infants and the elderly to conventional foods with high gel strength requirements. This greatly expands the application range of BCMPEs gels and surimi inks in food 3D printing and the production of various food products, significantly improving their overall performance.

[0074] The preparation method of BCSPEs gel is carried out by selecting any one of the three steps a', b', and c':

[0075] a' step, using 600 mmol / L KCl solution to prepare a 1%-4% (w / v) concentration of BCS particle suspension, after magnetic stirring, adjust the suspension to a neutral pH, hydrate for 24 hours, add soybean oil at an oil-water ratio of 5:5 (v / v), and homogenize to obtain BCSPEs gel;

[0076] b' step, using 200-1000 mmol / L KCl solution to prepare a 2% (w / v) concentration of BCS particle suspension, after magnetic stirring, adjust the suspension to a neutral pH, hydrate for 24 hours, add soybean oil at an oil-water ratio of 6:4 (v / v), and homogenize to obtain BCSPEs gel;

[0077] In step c', a 2% (w / v) concentration of BCS particle suspension was prepared using 600 mmol / L KCl solution. After magnetic stirring, the pH of the suspension was adjusted to neutral. After hydration for 24 hours, 5-20 U / g of transglutaminase and soybean oil with an oil-to-water ratio of 6:4 (v / v) were added, and the suspension was homogenized to obtain a BCSPEs gel.

[0078] In some specific embodiments, the method for preparing BCS particles comprises:

[0079] S101', cleaning the bighead carp, removing the head, tail and internal organs, and then collecting the meat to obtain bighead carp minced meat;

[0080] S102′, rinsing the minced meat with ice water at a material-liquid ratio of 1:5 (w / v) for 30-60 minutes, repeating three times, dehydrating, adding 4% (w / w) sorbitol, 4% (w / w) sucrose, 0.2% (w / w) sodium pyrophosphate, and 0.2% (w / w) sodium tripolyphosphate, and chopping and mixing uniformly;

[0081] S103', BCS particles were obtained after freeze-drying.

[0082] S200, thawing and crushing the bighead carp surimi, adding 10%-30% (w / w) BCMPEs gel or BCSPEs gel and mixing until uniform, to obtain bighead carp low-fat emulsion gel surimi ink;

[0083] In some specific embodiments, the pretreatment comprises thawing the frozen bighead carp surimi at 4°C for 12 hours, cutting into 2×2×2 cm 3 The cubes were pounded in a mortar for 5 minutes, and then 2.5% (w / w) edible salt was added and pounded for another 15 minutes.

[0084] Specifically, 200g of frozen bighead carp surimi was thawed at 4°C for 12 hours. The thawed surimi was cut into 2cm cubes and pounded in a mortar for 5 minutes. Table salt was then added at a rate of 2.5% by weight of the surimi, and pounded for another 15 minutes. A 10%-30% by weight fraction of a bighead carp low-fat Pickering emulsion gel was added to the surimi and stirred until uniformly dispersed, thereby obtaining a surimi ink containing the bighead carp low-fat Pickering emulsion gel. The bighead carp low-fat Pickering emulsion gel was either a BCMPEs gel or a BCSPEs gel.

[0085] In a second aspect, an embodiment of the present invention provides a surimi ink of a bighead carp low-fat emulsion gel, which is prepared by the preparation method described in the first aspect.

[0086] In some specific embodiments, the surimi ink has a moisture content of 75-90%, and is made of bighead carp surimi and 10%-30% by weight of bighead carp low-fat Pickering emulsion gel, where the bighead carp low-fat Pickering emulsion gel is any one of BCMPEs gel and BCSPEs gel.

[0087] Specifically, the weight fraction of the bighead carp low-fat Pickering emulsion gel is 20%. Preferably, the weight fraction of the BCMPEs gel is 20%.

[0088] In a third aspect, an embodiment of the present invention proposes an application of a small carp low-fat emulsion gel surimi ink, and an application of the small carp low-fat emulsion gel surimi ink prepared by the preparation method described in the first aspect in 3D printing.

[0089] In some specific embodiments, the 3D printing parameters include a nozzle diameter of 1.55 mm, a syringe barrel diameter of 28 mm, a layer thickness of 1.55 mm, a wall thickness of 4.65 mm, a bottom and top layer thickness of 3.1 mm, a filling density of 80%, and a printing speed of 15 mm / s.

[0090] Example 1

[0091] Step 1: Preparation of bighead carp myosin (BCM) pellets: 200 g of bighead carp dorsal white muscle was added to 10 volumes of 0.1 mol / L KCl and 20 mmol / L Tris-HCl buffer (pH 7.5). The pellet was homogenized in a food processor for 2 minutes. The homogenate was incubated at 4°C for 15 minutes, then filtered to remove the sarcolemma. The pellet was centrifuged at 10,000 × g for 20 minutes, and the supernatant was removed to collect the precipitate. The pellet was suspended in 5 volumes of 20 mmol / L Tris-HCl buffer (pH 6.8, containing 0.45 mol / L KCl, 5 mmol / L β-ME, 0.2 mol / L mg(CH3COO)2, and 1 mmol / L EGT). ATP-Na2 was added to dissociate myosin from actin. The final concentration of ATP-Na2 was controlled to be 10 mmol / L. After incubation at 4°C for 90 minutes, the supernatant was centrifuged at 10,000 × g for 20 minutes. The supernatant was diluted with 7 volumes of 1 mmol / L KHCO₃, incubated at 4°C for 2 hours, and then centrifuged at 10,000 × g for 20 minutes to collect the precipitate. The precipitate was then suspended in 2.5 volumes of 20 mmol / L Tris-HCl buffer (pH 7.5, containing 0.5 mol / L KCl and 5 mmol / L β-ME) and incubated at 4°C for 10 minutes. Five volumes of 1 mmol / L KHCO₃ were added to dilute the supernatant, and MgCl₂·6H₂O powder was added to a final concentration of 20 mmol / L. The supernatant was incubated at 4°C overnight, and then centrifuged at 10,000 × g for 20 minutes to collect the precipitate. This purified bighead carp myosin was then freeze-dried to obtain BCM pellets.

[0092] Step 2, preparation of bighead carp myosin Pickering emulsion (BCMPEs) gel: use 600 mmol / L KCl solution to prepare 2% (w / v) concentration of BCM particle suspension, magnetic stirring for 2 hours, adjust pH 7 with 1 mol / L HCl and NaOH solution, hydrate at 4°C for 24 hours, add 15 U / g of glutamine aminotransferase, add soybean oil at an oil-water ratio of 6:4 (v / v), and homogenize at 22000 r / min for 2 minutes to prepare BCMPEs gel.

[0093] Step 3, preparation of surimi ink: take out frozen bighead carp surimi (200g) and thaw it at 4℃ for 12h, cut it into 2×2×2cm 3 The cubes were crushed in a mortar for 5 minutes, and then 2.5% (w / w) edible salt was added and crushed for another 15 minutes. 10% (w / w) BCMPEs gel was added to the surimi and mixed until uniform. The overall moisture content of the final surimi ink was controlled at 80%.

[0094] Step 4: Application of surimi ink in 3D printing: The prepared surimi ink was printed using a single nozzle on a food 3D printer. The 3D printed models included a cylinder, a butterfly, a four-leaf clover, and a mouse. The following 3D printing parameters were optimized in preliminary experiments: nozzle diameter 1.55 mm, syringe barrel diameter 28 mm, layer thickness 1.55 mm, wall thickness 4.65 mm, bottom and top layer thickness 3.1 mm, infill density 80%, and print speed 15 mm / s. To facilitate the measurement of experimental parameters for the 3D printed models, the surimi ink used to print the cylindrical model was heated in a water bath at 40°C for 1 hour, followed by a water bath at 90°C for 15 minutes. The prepared surimi gel was cooled to room temperature in ice water to obtain the surimi gel product.

[0095] Example 2

[0096] The difference from Example 1 is that in step 3, 20% (w / w) BCMPEs gel is added to the surimi and mixed until uniform; the other steps are consistent with Example 1.

[0097] Example 3

[0098] The difference from Example 1 is that in step 3, 30% (w / w) BCMPEs gel is added to the surimi and mixed until uniform; the other steps are consistent with Example 1.

[0099] Example 4

[0100] The difference from Example 1 is that in step 3, 25% (w / w) BCMPEs gel is added to the surimi and mixed until uniform; the other steps are consistent with Example 1.

[0101] Example 5

[0102] The difference from Example 1 is:

[0103] Step 1: Wash the bighead carp with ice water, remove the head, tail, and internal organs, and use a meat extractor to extract the meat. Rinse the minced meat with ice water at a material-to-liquid ratio of 1:5 (w / v) for 30 minutes, and repeat this step three times. The minced meat is then dehydrated using a dehydrator. The dehydrated minced fish is placed in a chopper and mixed with 4% (w / w) sorbitol, 4% (w / w) sucrose, 0.2% (w / w) sodium pyrophosphate, and 0.2% (w / w) sodium tripolyphosphate. The mixture is then chopped and mixed evenly, stored at -20°C, and freeze-dried to obtain BCS particles.

[0104] Step 2, preparation of bighead carp surimi Pickering emulsion (BCSPEs) gel: Use 600 mmol / L KCl solution to prepare 2% (w / v) concentration of BCS particles, magnetically stir for 2 hours, adjust the pH to 7 with 1 mol / L HCl and NaOH solution, hydrate at 4°C for 24 hours, add 15 U / g of glutamine transaminase, add soybean oil at an oil-water ratio of 6:4 (v / v), and homogenize at 22000 r / min for 2 minutes to prepare BCSPEs gel.

[0105] Step 3, preparation of surimi ink: take out frozen bighead carp surimi (200g) and thaw it at 4℃ for 12h, cut it into 2×2×2cm 3 The cubes were crushed in a mortar for 5 minutes, and then 2.5% (w / w) edible salt was added and crushed for another 15 minutes. 10% (w / w) BCSPEs gel was added to the surimi and mixed until uniform. The moisture content of the surimi ink was controlled at 80%.

[0106] The remaining steps remain the same as in Example 1.

[0107] Example 6

[0108] The difference from Example 5 is that in step 3, 20% (w / w) BCSPEs gel is added to the surimi and mixed until uniform; the other steps are consistent with Example 1.

[0109] Example 7

[0110] The difference from Example 5 is that in step 3, 30% (w / w) BCSPEs gel is added to the surimi and mixed until uniform; the other steps are consistent with Example 1.

[0111] Example 8

[0112] The difference from Example 1 is that in step 2, a 1% (w / v) concentration of BCM particle suspension was prepared using 600 mmol / L KCl solution, magnetically stirred for 2 h, adjusted to pH 7 with 1 mol / L HCl and NaOH solutions, hydrated at 4°C for 24 h, and soybean oil was added at an oil-water ratio of 5:5 (v / v). The BCMPEs gel was prepared by homogenization at 22,000 rpm for 2 min.

[0113] Example 9

[0114] The difference from Example 8 is that in step 2, a BCM particle suspension with a concentration of 2% (w / v) is prepared.

[0115] Example 10

[0116] The difference from Example 8 is that in step 2, a BCM particle suspension with a concentration of 4% (w / v) is prepared.

[0117] Example 11

[0118] The difference from Example 8 is that the BCM particle suspension in step 2 is replaced by BCS particle suspension, and the BCMPEs gel in step 3 is replaced by BCSPEs gel.

[0119] Example 12

[0120] The difference from Example 1 is that in step 2, a 2% (w / v) concentration of BCM particle suspension was prepared using 200 mmol / L KCl solution, magnetically stirred for 2 h, adjusted to pH 7 with 1 mol / L HCl and NaOH solutions, hydrated at 4°C for 24 h, and soybean oil was added at an oil-water ratio of 6:4 (v / v). The BCMPEs gel was prepared by homogenization at 22,000 rpm for 2 min.

[0121] Example 13

[0122] The difference from Example 12 is that in step 2, a 2% (w / v) concentration of BCM particle suspension is prepared using a 600 mmol / L KCl solution.

[0123] Example 14

[0124] The difference from Example 12 is that in step 2, a 1000 mmol / L KCl solution is used to prepare a 2% (w / v) concentration of BCM particle suspension.

[0125] Example 15

[0126] The difference from Example 12 is that the BCM particle suspension in step 2 is replaced by BCS particle suspension, and the BCMPEs gel in step 3 is replaced by BCSPEs gel.

[0127] Example 16

[0128] The difference from Example 1 is that 5 U / g of transglutaminase is added in step 2.

[0129] Example 17

[0130] The difference from Example 1 is that 20 U / g of transglutaminase is added in step 2.

[0131] Example 18

[0132] The difference from Example 1 is that, in step 3, the overall moisture content of the surimi ink finally obtained is controlled at 75%.

[0133] Example 19

[0134] The difference from Example 1 is that in step 3, the overall moisture content of the surimi ink finally obtained is controlled at 90%.

[0135] Blank group

[0136] Bighead carp surimi without bighead carp low-fat Pickering emulsion gel and soybean oil was used as the blank group.

[0137] control group

[0138] Only 6% (w / w) soybean oil was added to bighead carp surimi as a control group.

[0139] The surimi inks and surimi gels prepared in Examples 1-3, the experimental group (Example 6), the blank group, and the control group were analyzed in the following order: first, the rheological properties and 3D printing adaptability of the surimi inks were characterized using a rheometer and a food 3D printer; second, the whiteness, moisture distribution, and texture properties of the surimi gel were analyzed using a colorimeter, a low-field nuclear magnetic resonance analyzer, and a texture analyzer; third, the micromorphology of the surimi gel was characterized by confocal laser scanning microscopy and a scanning electron microscope; finally, the dysphagia level of the surimi gel was evaluated according to the International Dysphagia Diet Standardization Initiative (IDDSI).

[0140] refer to Figure 2 , Figure 2 The rheological properties of the surimi ink according to Examples 1-3, the experimental group, the blank group and the control group are shown. Figure 2 A is the apparent viscosity diagram, Figure 2 B is the strain scan diagram, Figure 2 C is the frequency scan diagram, Figure 2 D is a three-segment thixotropy scan. During the 3D printing process, apparent viscosity has a significant impact on product quality. High apparent viscosity increases the friction of the sample during extrusion and reduces the extrusion speed. All surimi ink samples exhibit shear thinning properties, that is, the apparent viscosity decreases with increasing shear rate (see Figure 2 A). At the same shear rate, the apparent viscosity of the blank and control groups was higher. After adding BCMPEs gel and BCSPEs gel, the apparent viscosity of the surimi ink decreased, which is more conducive to printing through a smaller diameter nozzle during the printing process. Strain sweeps were used to determine the linear viscoelastic region of the surimi ink and study the storage modulus (G') and loss modulus (G") of surimi inks with different BCMPEs gel contents within the shear strain range of 0.01-100% (see for details). Figure 2 B). When the shear strain is ≤1%, the G' and G" of all surimi ink samples remain basically stable, and this range is the linear viscoelastic region. To further explore the network structure of surimi ink, a frequency sweep was performed with a shear strain of 1%, and the G' and G" of all samples were analyzed at angular frequencies of 0.1-100 rad / s (see Figure 2C). In the low angular frequency range, G' and G" rise rapidly. This is because the low angular frequency cannot completely destroy the network structure of the fish paste ink. As the angular frequency increases, G' and G" gradually stabilize and G' is greater than G", indicating that the fish paste ink has solid-like properties and strong elasticity. Higher G' and G" help improve the quality of 3D printed products, but due to the presence of water and oil phases in the emulsion gel, at the same angular frequency, the G' and G" of the fish paste ink will decrease with the increase of the BCMPEs gel content. The G' and G" of the fish paste ink in the experimental group with 20% BCSPEs gel are similar to those in the group with 20% BCMPEs gel. An ideal 3D printing material should have good shear recovery behavior, so that it has a low apparent viscosity during extrusion and is easy to flow. After extrusion, it can quickly recover a high apparent viscosity to improve the stacking ability between layers. In order to simulate the shear state during 3D printing, a three-step thixotropy scan (Three-Step Thixotropy Test, 3ITT, see for details) was performed on the fish paste ink. Figure 2 D) First, a low shear rate of 0.1s-1 was applied to simulate the initial extrusion state of the surimi ink in the syringe; then, the shear rate was increased to 10s-1. -1 , simulating its extrusion state at the nozzle tip; finally, the shear rate was reduced to 0.1s -1 , simulating the recovery behavior and post-printing state of surimi ink. The thixotropic recovery rate is the ratio of the apparent viscosity in the third stage to the apparent viscosity in the first stage. A thixotropic recovery rate exceeding 70% indicates good thixotropic recovery. Calculations show that surimi inks with only 20% BCMPEs gel content and the experimental group's surimi inks have thixotropic recovery rates exceeding 70%, indicating that the appropriate amount of BCMPEs gel added during 3D printing ensures that the surimi ink maintains high structural stability under gravity and sedimentation.

[0141] Figure 3 The model diagrams of surimi ink 3D printed products according to Examples 1-3 of the present invention, the experimental group, the blank group and the control group are shown. A good 3D printed product should have the characteristics of stable structure, smooth surface, uniform filaments, perfect details and the like. In order to evaluate the adaptability of surimi ink 3D printing, surimi inks with different BCMPEs gel contents were used to print cylinder, butterfly, four-leaf clover and mouse models, and the results are shown in the figure. Due to the shear thinning properties, all surimi ink groups can be extruded through the nozzle. The surimi ink in the blank group has a high apparent viscosity, and the ink fluidity and uniformity are poor during the extrusion process, resulting in an uneven surface of the printed sample and flaws in the details. The control group only added soybean oil, and the surimi ink was prone to discontinuous extrusion and even nozzle clogging during printing. The 3D printing adaptability was poor, and the printed products were prone to collapse and incomplete shapes (such as Figure 3(Indicated by the red arrow in the control group). Compared with the control group, the addition of 10% BCMPEs gel allowed the surimi ink to extrude more smoothly, with fine and smooth lines, significantly improving the continuity of 3D printing and reducing the surface roughness of the product. As the BCMPEs gel content increased to 20-30% and in the experimental group, the surimi ink achieved the highest 3D printing accuracy and the best product shape. Because BCMPEs and BCSPEs gels reduced the apparent viscosity and storage modulus (G') of the surimi ink, they improved its texture and enabled it to be extruded smoothly during the 3D printing process. Furthermore, its high thixotropic recovery ability also gave it good 3D printing adaptability. However, when the BCMPEs gel content reached 30%, the surimi ink's support capacity decreased, and the stability of the printed product decreased. This may be because the excessive BCMPEs gel significantly weakened the mechanical strength of the surimi ink, thereby reducing the product's printing quality.

[0142] refer to Figure 4 , Figure 4 The results of the 3D printing accuracy and stability analysis of the surimi ink according to Examples 1-3 of the present invention, the experimental group, the blank group, and the control group are shown. As the BCMPEs gel content increases and in the experimental group, the height of the surimi ink printed product gradually approaches the preset value, and the 3D printing accuracy is significantly improved (P < 0.05) (e.g. Figure 4 A). However, the trend of 3D printing stability is opposite to that of accuracy (see Figure 4 B) The surimi ink in the blank group showed the highest 3D printing stability, thanks to its strong mechanical properties, which ensured excellent stability of the printed product. However, the surimi ink's 3D printing stability gradually decreased with increasing BCMPEs gel content, as the aqueous and oily phases in the BCMPEs gel reduced the mechanical properties of the surimi ink.

[0143] Continue to refer Figure 5 , Figure 5The water holding capacity (WHC) and cooking loss (CL) of the surimi gel according to Examples 1-3 of the present invention, the experimental group, the blank group and the control group are shown. The WHC of the surimi gel reflects the binding ability of its gel network with water molecules. The dense and ordered gel network structure can intercept more water molecules and reduce the mobility of water molecules. The control group only added soybean oil, and its surimi gel had the lowest WHC, indicating that the gel structure was poor. This is because the presence of large oil droplets increased the distance between proteins, causing the gel network structure to loosen and the uniformity to decrease. Compared with the blank group and the control group, the surimi gel after adding BCMPEs and BCSPEs gel had a higher WHC. This is because the droplet size of BCMPEs and BCSPEs gel is small and evenly distributed in the surimi gel, which effectively reduces the isolation effect of the oil droplets and promotes the cross-linking between myofibrillar protein molecules. At the same time, the hydrophilic groups on the surface of the protein in the droplet interface layer can tightly bind to the water in the gel matrix through hydrogen bonds. The loss of water, oil, and other substances during cooking can affect food quality. CL reflects the stability of the product during processing, and CL is usually negatively correlated with WHC. The control group had the highest CL (7.12%), which was consistent with the WHC results. Large oil droplets hinder the cross-linking of protein molecules and weaken the network structure of the surimi gel matrix, resulting in an increase in CL. After adding BCMPEs gel (10-20%), the CL of the surimi gel continued to decrease, reaching a minimum value (4.74%) when the BCMPEs gel content was 20%, which was not significantly different from the CL of the experimental group (P ≥ 0.05). This is due to the good thermal stability of BCMPEs gel, which enhances the network structure of the surimi gel matrix and improves the water and oil holding capacity. However, when the BCMPEs gel content continued to increase to 30%, the CL of the surimi gel further increased.

[0144] Low-field nuclear magnetic resonance (LF-NMR) technology was used to evaluate the water distribution and nuclear magnetic resonance imaging of surimi gels with different BCMPEs gel contents. Figure 6 As shown in Figure 2, the T2 relaxation time of all surimi gel samples showed three peaks: T 21 (0-10ms) represents the bound water tightly bound to the protein macromolecule, T 22 (10-100ms) represents the fixed water in the gel network structure, T 23 (100-1000ms) represents the free water in the gel network structure. Compared with the blank group, the T 23 The peak shifts to longer relaxation times (see Figure 6A), the peak area ratio increases, which indicates that the free soybean oil weakens the density of the fish surimi gel network structure, reduces the exposure of the hydrophilic groups in the fish surimi gel, is not conducive to the fixation of water, and thus increases the free water content. With the increase of BCMPEs gel content (10-20%) and in the experimental group, T 23 The peak shifts to shorter relaxation times, T 22 The peak area ratio increased significantly (P < 0.05) (see Figure 6 B). This is because BCMPEs gel can be evenly distributed in the surimi gel matrix. Studies have shown that regular and orderly gel network structures can better restrict water flow. However, when the BCMPEs gel content continues to increase to 30%, the ability of surimi gel to bind water decreases. This is because the overfilling of BCMPEs gel puts pressure on the gel network structure, destroying its integrity and causing some water loss. Nuclear magnetic resonance imaging (MRI) can display proton density-weighted images inside the sample, visualizing the distribution of hydrogen protons in the sample. The more hydrogen protons there are, the redder the pseudo-color image is. Generally, low signal intensity (blue area) represents relatively free water, and high signal intensity (red area) represents bound water or fixed water. Compared with the blank group, the red dots in the pseudo-color image of the control group are fewer and unevenly distributed (see for details). Figure 6 C), indicating uneven water distribution and low water holding capacity. After adding BCMPEs gel, the red area in the pseudo-color image of the surimi gel increased, indicating that BCMPEs gel improved the water distribution of the surimi gel. The red area was most pronounced in the 20% BCMPEs gel content and the experimental group, indicating a more uniform distribution of hydrogen protons. However, when the BCMPEs gel content increased to 30%, the red area in the surimi gel decreased, indicating a decrease in uniformity.

[0145] Confocal laser scanning microscopy (CLSM) was used to observe the distribution of protein and oil droplets in surimi gels with different BCMPEs gel contents. Figure 7 . The size and distribution of oil droplets are key factors affecting the performance of surimi gel. The direct addition of soybean oil in the control group resulted in large, irregularly shaped and unevenly distributed oil droplets, which weakened the network structure of the surimi gel, indicating that the direct addition of soybean oil is not conducive to the formation of a dense and uniform gel network structure. Compared with the control group, at the same oil content, the surimi gel with 10% BCMPEs gel added had small droplets, regular shapes and uniformly distributed in the gel matrix. As the BCMPEs gel content continued to increase and in the experimental group, the number of droplets in the surimi gel increased and the distribution became more uniform.

[0146] The gel strength and texture profile analysis (TPA) characteristics of surimi gels with different BCMPEs gel contents were measured. The results are shown in Table 1 below:

[0147] Table 1 Gel strength and TPA of surimi gel at different BCMPEs gel contents

[0148]

[0149] Compared with the blank group, the control group directly added soybean oil, resulting in a significant decrease in the gel strength, hardness, elasticity, cohesion and chewiness of the surimi gel (P < 0.05). Generally speaking, the addition of soybean oil will interfere with the interaction of proteins in the surimi gel matrix, hinder the construction of the gel network, and thus lead to the deterioration of the gel structure. The micromorphology analysis results of the surimi gel (see Figure 7 ) provides strong evidence for this. Under the same oil content, surimi gels containing 10% BCMPEs gel exhibited significantly higher gel strength, hardness, and elasticity than the control group (P < 0.05). Elasticity refers to the ability of an object to return to its original shape after deformation due to an external force. This suggests that BCMPEs gel can improve the structural degradation of surimi gels caused by the addition of oil and enhance their resilience. In Pickering emulsions, oil is encapsulated by a protein membrane to form stable droplets, which reduces oil interference with myofibrillar protein gelation. Furthermore, the solid structure of BCMPEs gel can evenly fill the voids in the surimi gel network, thereby improving the gel strength and texture profile analysis (TPA) properties of the surimi gel. When the BCMPEs gel content was further increased to 20-30%, the gel strength of the surimi gel gradually decreased. The surimi gel strength of the experimental group was not significantly different from that of the 20% BCMPEs gel group (P ≥ 0.05). This property could help develop soft surimi products rich in a high proportion of functional lipids, which could be used as functional foods for young children or the elderly.

[0150] Figure 8 Scanning electron microscope (SEM) images of the surimi gels according to Examples 1-3 of the present invention, the experimental group, the blank group, and the control group are shown. SEM presents high-resolution images of the gel network structure, which facilitates the observation of key microstructural features such as pore size and distribution. As shown in the figure, the network structure of the surimi gel in the blank group is uniform and dense; while the surimi gel in the control group has larger and irregularly shaped pores. This is because during the thermally induced gelation of the surimi, unstable oil droplets easily migrate and aggregate within the gel matrix, increasing the distance between proteins and causing the gel structure to be loose and irregular. This structural feature also corresponds to the results of low water holding capacity (WHC) and high cooking loss (CL) (see for details). Figure 5Compared to the control group, the pore size of the surimi gel containing 10% BCMPEs gel decreased further at the same oil content, indicating that BCMPEs gel significantly improved the density and uniformity of the surimi gel network structure. As the BCMPEs gel content increased to 20-30%, and in the experimental group, the number of pores in the surimi gel gradually increased.

[0151] The IDDSI test provides a globally unified terminology and classification standard for food texture, facilitating a quick assessment of food suitability for dysphagia patients. The fork drop test, spoon tilt test, and fork pressure test were used to evaluate the dysphagia food grade of surimi gels with different BCMPEs gel contents. Figure 9 As shown. In the fork drop test, all surimi gel groups were able to stack on the fork without sliding down the fork slit, indicating that the surimi gels can be classified as potential Class 5 / 6 / 7 foods within the IDDSI framework. The spoon tilt test, which assesses the viscosity and cohesion of the surimi gels, showed that all surimi gel groups had sufficient cohesion to maintain their shape on the spoon. When the spoon was tilted and gently shaken, the surimi gel samples easily slid off the spoon without residue, which facilitates swallowing for individuals with dysphagia by preventing food from sticking to the tongue or pharynx. In the fork pressure test, the pressure that causes the thumb to turn white is similar to the pressure exerted by the tongue when squeezing food during swallowing. The results showed that the surimi gels in the blank and control groups largely returned to their original shape after the fork was removed, leaving a noticeable indentation, and therefore did not fall into the Class 6 / 7 category of the IDDSI. In contrast, the surimi gels in the experimental group and those containing BCMPEs gel flattened and deformed when the thumb tip turned white, and did not return to their original shape after the fork was removed. As the BCMPEs gel content increased, the surimi gel was seen to be cut, meeting the definition of grade 6 / 7 dysphagia food (soft and bite-sized / easy to chew). These results indicate that 3D-printed surimi-emulsion gel is suitable for patients with dysphagia.

[0152] In the present invention, BCMPEs gel is evenly distributed in the surimi gel, which improves the whiteness of the surimi gel and reduces the strength, hardness and chewiness of the gel. In view of the small droplet size and solid gel properties of BCMPEs gel, it can fill the gaps in the surimi gel network, enhance the density of the gel network, and thus limit the movement of water molecules in the gel matrix. The surimi gel with a 20% BCMPEs gel content exhibits the characteristics of high water holding capacity (WHC) and low cooking loss (CL). Compared with the blank group and the control group, the surimi gel after adding BCMPEs and BCSPEs gel could not return to its original shape after the fork pressure test, and the phenomenon of being cut was clearly observed. According to the International Dysphagia Diet Standardization Initiative (IDDSI) framework, it can be classified as a level 6 / 7 (soft and bite-sized / easy to chew) dysphagia food. Overall, the appropriate amount of BCMPEs gel significantly improved the 3D printing adaptability and gel properties of surimi inks. This also confirmed the feasibility of surimi particles stabilizing Pickering emulsion gels, supporting their practical application in food industry production. This research provides a theoretical basis for producing surimi products that meet lipid requirements and possess 3D printing characteristics.

[0153] Obviously, those skilled in the art can make various modifications and changes to the embodiments of the present invention without departing from the spirit and scope of the present invention. In this way, if these modifications and changes are within the scope of the claims of the present invention and their equivalents, the present invention is also intended to cover these modifications and changes. The word "comprising" does not exclude the presence of other elements or steps not listed in the claims. The simple fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be considered as limiting the scope.

Claims

1. A fish paste ink of bighead carp low-fat emulsion gel, characterized in that: The surimi ink has a water content of 75-90% and is prepared from bighead carp surimi and 10-30% by weight of bighead carp low-fat Pickering emulsion gel, wherein the bighead carp low-fat Pickering emulsion gel is any one of BCMPEs gel and BCSPEs gel.

2. The fish paste ink of bighead carp low-fat emulsion gel according to claim 1, characterized in that: The weight fraction of the bighead carp low-fat Pickering emulsion gel is 20%, wherein the weight fraction of the BCMPEs gel is 20%.

3. The method for preparing the surimi ink of bighead carp low-fat emulsion gel according to any one of claims 1-2, characterized in that: The preparation method comprises: S1, preparing a 1-4% (w / v) concentration of a BCM particle suspension or a BCS particle suspension using a 200-1000 mmol / L KCl solution, adjusting the suspension to a neutral pH after magnetic stirring, adding soybean oil after hydration for 24 hours, and homogenizing to obtain the BCMPEs gel or the BCSPEs gel; S2, after pre-treatment by thawing and crushing bighead carp surimi, adding 10%-30% (w / w) of the BCMPEs gel or the BCSPEs gel and mixing until uniform, to obtain the bighead carp low-fat emulsion gel surimi ink.

4. The method for preparing a small carp low-fat emulsion gel surimi ink according to claim 3, characterized in that: In the step S1, the soybean oil and 5-20 U / g of transglutaminase are added after hydration for 24 hours, and the BCMPEs gel or the BCSPEs gel is obtained after homogenization.

5. The method for preparing a small carp low-fat emulsion gel surimi ink according to claim 3, characterized in that: The soybean oil is added at an oil-water ratio of 5:5-6:4 (v / v), and the BCMPEs gel or the BCSPEs gel is obtained after homogenization.

6. The method for preparing a bighead carp low-fat emulsion gel surimi ink according to claim 3, characterized in that: The pretreatment of the S2 step includes: Thaw the frozen bighead carp surimi at 4°C for 12 h and cut into 2 × 2 × 2 cm 3 The cubes were pounded in a mortar for 5 minutes, and then 2.5% (w / w) edible salt was added and pounded for another 15 minutes.

7. The method for preparing a bighead carp low-fat emulsion gel surimi ink according to claim 3, characterized in that: The preparation method of the BCMPEs gel is implemented by selecting any one of the three steps a, b, and c: In step a, a 1%-4% (w / v) concentration of BCM particle suspension is prepared using a 600 mmol / L KCl solution. After magnetic stirring, the pH of the suspension is adjusted to neutral. After hydration for 24 hours, soybean oil is added at an oil-water ratio of 5:5 (v / v), and the BCMPEs gel is obtained after homogenization; Step b: preparing a 2% (w / v) concentration of BCM particle suspension using a 200-1000 mmol / L KCl solution, adjusting the suspension to a neutral pH after magnetic stirring, hydrating for 24 hours, adding soybean oil at an oil-water ratio of 6:4 (v / v), and homogenizing to obtain the BCMPEs gel; Step c: a 2% (w / v) BCM particle suspension was prepared using a 600 mmol / L KCl solution. After magnetic stirring, the pH of the suspension was adjusted to neutral. After hydration for 24 hours, 5-20 U / g of transglutaminase and soybean oil with an oil-water ratio of 6:4 (v / v) were added, and the BCMPEs gel was obtained after homogenization. The preparation method of the BCSPEs gel is implemented by selecting any one of the three steps a', b', and c': a' step, preparing a 1%-4% (w / v) concentration of BCS particle suspension using 600 mmol / L KCl solution, adjusting the suspension to a neutral pH after magnetic stirring, hydrating for 24 hours, adding soybean oil at an oil-water ratio of 5:5 (v / v), and homogenizing to obtain the BCSPEs gel; b' step, preparing a 2% (w / v) concentration of BCS particle suspension using a 200-1000 mmol / L KCl solution, adjusting the suspension to a neutral pH after magnetic stirring, hydrating for 24 hours, adding soybean oil at an oil-water ratio of 6:4 (v / v), and homogenizing to obtain the BCSPEs gel; In step c', a 2% (w / v) concentration of BCS particle suspension was prepared using a 600 mmol / L KCl solution. After magnetic stirring, the pH of the suspension was adjusted to neutral. After hydration for 24 hours, 5-20 U / g of transglutaminase and soybean oil with an oil-to-water ratio of 6:4 (v / v) were added, and the BCSPEs gel was obtained after homogenization.

8. The method for preparing a bighead carp low-fat emulsion gel surimi ink according to claim 3, characterized in that: The preparation method of the BCM particles comprises: S11, taking 150-250 g of white muscle from the back of bighead carp, adding buffer 1 (pH 7.5) prepared from 0.08-0.12 mol / L KCl and 20 mmol / L Tris–HCl, homogenizing, filtering, and centrifuging to obtain precipitate 1; S12, suspending the precipitate 1 in a buffer 2 having a pH of 6.8-7.0 prepared from 0.4-0.5 mol / L KCl, 4-6 mmol / L β-ME, 0.18-0.22 mol / LMg(CH3COO)2, and 0.8-1.2 mmol / L EGTA, and adding ATP-Na2 to a final concentration of 8-12 mmol / L ATP-Na2 to obtain a mixed solution; S13, incubating the mixture at 3-5°C for 80-100 minutes, centrifuging, and diluting the collected supernatant with 1 mmol / L KHCO3. The mixture was then placed at 4°C for 1.5-2.5 hours, and then centrifuged to obtain a second precipitate. S14, suspending the precipitate 2 in a buffer solution 3 at pH 7.5 containing 0.45-0.55 mol / L KCl and 4-6 mmol / L β-ME, and placing the suspension at 4°C for 10 min. 1 mmol / L KHCO3 was added for dilution, and MgCl2·6H2O solid powder was added to a final concentration of 18-22 mmol / L. The suspension was allowed to stand at 4°C overnight to obtain a BCM suspension. S15, collecting the centrifugal precipitate of the BCM suspension, and freeze-drying it to obtain the BCM particles.

9. Application of a bighead carp low-fat emulsion gel surimi ink, characterized in that: Use of the surimi ink of the bighead carp low-fat emulsion gel according to any one of claims 1-2 or the surimi ink of the bighead carp low-fat emulsion gel prepared according to the preparation method according to any one of claims 3-7 in 3D printing.

10. The use of the bighead carp low-fat emulsion gel surimi ink according to claim 9, characterized in that: The 3D printing parameters include a nozzle diameter of 1.55 mm, a syringe barrel diameter of 28 mm, a layer thickness of 1.55 mm, a wall thickness of 4.65 mm, a bottom and top layer thickness of 3.1 mm, a filling density of 80%, and a printing speed of 15 mm / s.

Images